High hopes, but expectations are low for Britain's smaller parties..

The SNP will record their second best ever performance in a Westminster election on June 8th, with dozens of nationalist MPs jumping on trains down to London. And yet it will represent a weakening of their position, curbing hopes of triggering a second independence referendum.

Winning all but 3 Scottish seats in 2015 means the only way is down for Nicola Sturgeon’s party. They'll fight hard for the handful of seats they don't already have, but the Conservatives, once virtually extinct across Scotland, are poised to pick up anything up to a dozen seats.

The Tories are solidifying their position as the main anti-SNP voice, and winning over Labour voters alienated by their lacklustre leadership. In Ruth Davidson they have a leader who appeals to many voters who would never consider themselves natural Conservatives, but rows over the "rape clause" benefit restrictions will harm an image she's worked hard to improve.

Even so, the SNP ought to be able to hold 45 seats, hugely impressive at any other time from a party that used to settle for 5 or 6.

But in 2017 that kind of performance could put dreams of independence on the back burner once again.

The Green Party became the fashionable protest party two years ago, mainly from disgruntled Lib Dems struggling to find a home.

Those days are in the past, and the party once again feels very much on the margins.

Caroline Lucas has every chance of winning in Brighton Pavilion again, but it’s hard to see how any other seats could be classified as vulnerable.

Instead, their main role could be as cheerleaders for other, anti-Brexit, candidates, whether Labour or Lib Dem, with Greens dropping out in their favour.